Summary The Scenic Air Services Ltd. float-equipped PiperPA-18-150 (registrationC-FIWV, serial number18-6299) departed Tootsie Lake, British Columbia, at 1119 Pacific daylight time on a day visual flight rules flight to Linda Lake, British Columbia. The purpose of the flight was to transport moose meat, antlers, and camp materials located at the outfitter's camp at Linda Lake, British Columbia to the outfitter's base camp at Tootsie Lake. The aircraft was not heard from after it departed Tootsie Lake. At 1228, the Search and Rescue Satellite System received an emergency locator transmitter signal, and the aircraft was subsequently reported overdue. A helicopter was chartered out of Watson Lake, Yukon, to conduct a search; the wreckage was found on the shoreline of Linda Lake at 1602. The aircraft was substantially damaged, and the pilot, the lone occupant, sustained fatal injuries. There was no post-impact fire. Ce rapport est galement disponible en franais. 1.0 Other Factual Information 1.1 History of the Flight The Scenic Air Services Ltd. float-equipped PiperPA-18-150 aircraft had been based at the Kawdy Outfitters base camp at Tootsie Lake, British Columbia, for the duration of the summer/fall hunting season. The aircraft was being operated under Canadian Aviation Regulation (CAR)703, Air Taxi Operations. The flight to Linda Lake was approximately 15miles, and this was the pilot's third return trip to Linda Lake that day and his fourth trip of the day overall. The flight was being conducted under day visual flight rules. The pilot intended to pick up moose meat, antlers, and camp supplies located at the outfitter's camp at Linda Lake and return to the outfitter's base camp at Tootsie Lake. The aircraft was not heard from after it departed Tootsie Lake. At 1228 Pacific daylight time,1 the Search and Rescue Satellite System received an emergency locator transmitter signal. At 1346, the outfitter contacted an air operator in Watson Lake, Yukon, by satellite telephone and reported the aircraft overdue. A helicopter was chartered out of Watson Lake to conduct a search; the wreckage was found at 1602 on the shoreline of Linda Lake. The aircraft was substantially damaged and the pilot, the lone occupant, had sustained fatal injuries. There was no post-impact fire. The outfitter's camp at Linda Lake was unoccupied at the time of the accident and there were no witnesses to the accident. 1.2 Injuries to Persons 1.3 Damage to Aircraft The damage patterns indicated that the aircraft struck the ground in a steep, right-wing-low attitude at low forward speed. The float struts collapsed at impact and the right wing sustained heavy impact damage. The cabin structure partially collapsed and the supporting structure on the pilot's seat buckled at impact, indicating high vertical deceleration forces. The flap handle was set in the second of three possible flaps-extended notches, indicating the flaps were at an intermediate position at impact. 1.4 Personnel Information The pilot was characterized as a skilled and cautious flyer, and a meticulous aircraft maintenance engineer. He held a commercial pilot licence valid for single-engine landplanes and seaplanes with a restriction for daylight flying only, and he held an aircraft maintenance engineer licence with an M1 category rating. He had obtained a private pilot licence in1971, and a commercial pilot licence and a float endorsement in1974. There were no entries in his pilot logbook for the period between September1977 and March1997, and there was nothing found to indicate he had acquired any commercial aviation experience between1977 and1997. Prior to commencing employment with Scenic Air Services Ltd. in the spring of1997, the pilot received 3.8hours of recurrent flight training on a wheel-equipped Cessna172, to return him to commercial pilot standards. There was no record of the pilot having received formal flight training subsequent to1997. The pilot was appointed Chief Pilot and Operations Manager of Scenic Air Services Ltd. in July1997. The appointment was approved subject to a Transport Canada review after six months; however, there was nothing found to indicate that a six-month review had been performed. At the time of the accident, the pilot held the positions of Operations Manager, Chief Pilot, Director of Maintenance, Maintenance Manager, Quality Manager, Production Manager, and Stores Manager for the company. As such, he was responsible for all aspects of the company's aviation operations, including flight operations, maintenance, quality assurance, and training. 1.5 Aircraft Information Log entries indicate that the aircraft was certified and being maintained in accordance with existing regulations. The most recent 100-hour inspection had been completed 48.4hours before the accident, on 13September2003. There was no record of outstanding defects in the aircraft journey log. The aircraft airframe and systems were examined in the field. All flight and engine controls were continuous, and all damage to the aircraft was attributable to the severe impact forces. The aircraft had sufficient fuel for the intended flight. Propeller blade twist and leading edge damage indicated that the engine was likely operating at a mid-range power setting at impact. The engine (Lycoming0-320-A2B) was removed and transported to an engine overhaul facility for a test run. During the engine testing, it was determined that the right magneto was intermittently inoperative because of the grounding of the core wire to the shielding on the right magneto p-lead. The TSB Engineering Laboratory examined the p-lead and determined that several of the copper strands in the core wire were discontinuous at the aft end of the ferrule, where the lead attached to the magneto. As well, the insulation between the core and the shielding was broken and separated in that area, exposing the copper wire to the shield. The grungy appearance of the p-lead indicated it had been in service for a long time. No other significant pre-impact engine discrepancies were identified during the engine examination and test run. Communication with the engine manufacturer determined that the loss of one magneto on this model of engine would result in an estimated 9to 10percent reduction in available power at full throttle. The rear cockpit control stick had been removed, and a hand-fabricated aluminum protective cover had been installed over the rear stick socket to prevent cargo being carried in the rear seat area from jamming the flight controls. Visual examination of the inside of the protective cover showed that the top end of the stick socket had been contacting the rear wall of the cover when the control stick was pulled to the full-aft position. There was no indication that the protective cover had collapsed or was interfering with the rear stick socket during flight in a manner that would prevent normal operation of the flight controls. The aircraft was fitted with a six-foot-long cargo box mounted aft of the cabin in the rear fuselage. The installation resembled a ski cargo box that had been approved as a one-time installation in another PA-18 in1972, under approval numberW72-199. There was no record of the installation in the aircraft records. The ski cargo box was estimated to weigh nine pounds. It could not be determined if the aircraft was fitted with the cargo box when the aircraft was last weighed. The aircraft was also fitted with a VHF FM radio that was unaccounted for in the weight and balance reports. The aircraft was equipped with a McCauley1A175-GM8241 (Borer) propeller, in accordance with Supplemental Type Certificate (STC)SA279AL. However, the STC did not provide for operation of this propeller in combination with the Canadian Aircraft Products (CAP)67-2000 floats that were installed on the aircraft. The aircraft was not equipped with a stall warning system that would have warned the pilot of an impending stall, and a stall warning system was not required by regulation. This deficiency has been identified in the past in numerous accidents involving older light aircraft designs. 1.6 Weight and Balance The original production weight and balance report for the aircraft identified the datum as a point 60inches forward of the wing leading edge. The current Type Certificate Data Sheet for the PA-18-150, Aircraft Specification No.1A2, Revision37, identifies the datum as the wing leading edge. Some of the references in the original production weight and balance material use the point 60inches forward of the wing leading edge as the datum, while other references such as the original equipment list and the centre of gravity envelope chart use the wing leading edge as the datum. The aircraft had last been weighed on 18March1974. Between March1974 and August2001, the weight and balance report was amended three times. Each of the amended reports used the datum 60inches forward of the wing leading edge to report the empty weight centre of gravity; however, on two of the three amendments, the arms for the items listed were mixed between inches from the wing leading edge and inches aft of the datum, and the empty weight centre of gravity was erroneous. Aircraft maintenance personnel familiar with PA-18 aircraft have reported finding similar errors in PA-18 weight and balance amendments. There are currently 405Piper PA-18 aircraft in the Canadian registry, 42of which are registered for commercial purposes. The aircraft had been fitted with CAP67-2000 floats on 16August2001. Two weight and balance report amendments applicable to the float installation were found, both dated 16August2001. Both reports contained weight and centre of gravity discrepancies. The weight and balance report in the aircraft journey log indicated that the float installation weighed 236.0pounds, and that the empty weight of the aircraft was 1224.5pounds. The weight and balance report found in the aircraft technical log identified the weight of the float installation as 286.0pounds and identified the empty weight of the aircraft on floats as 1274.5pounds. Weight and balance data for the CAP67-2000 float installation identified that the floats weighed 290.0pounds and that the service step and paddle installation weighed an additional 2.5pounds. It was not determined if the pilot was aware of the errors in the amended weight and balance reports. The pilot frequently transported hunters and cargo between the main base camp and temporary outlying camps, and the nature of the work required that the weight of the cargo on each flight had to be estimated, as there was no convenient way to weigh each load before take-off. The cargo was removed from the aircraft and weighed at the accident site. One set of moose antlers, weighing 41pounds, was found secured to the right float struts. An additional 301 pounds of cargo, including moose meat, a moose cape, camp materials, and survival gear, was recovered from the rear seat area of the wreckage. The left float contained 37pounds of water. The pilot was in the habit of pumping the right float several times a day; however, the right float sustained substantial impact damage, and the amount of water in the float at impact could not be determined. The cabin load had not been restrained during flight. Weight and balance calculations completed by investigators, based on a review and correction of the aircraft's weight and balance historical documents, indicated the empty weight of the aircraft was, at a minimum, 1281pounds. It was calculated that the gross weight of the aircraft at the time of the accident was at least 1922pounds, and the centre of gravity was 17.0inches aft of the wing leading edge. The maximum certified seaplane take-off weight was 1760pounds, and the centre of gravity limits at that weight were 16.2to 20.0inches aft of the wing leading edge. Operating an aircraft at a weight that exceeds the maximum take-off weight will reduce the aircraft's climb performance, adversely affect stability and slow flight characteristics, and increase the stall speed. 1.7 Meteorological Information The ceiling and visibility at the time of the accident were suitable for flight in accordance with visual flight rules. Hunting guides working in the area described the midday visibility as unrestricted and the sky conditions as almost clear, with patches of high cloud. The surface winds were generally from the south or west for most of the day, at speeds estimated to be between 10to 30mph, and gusting. The variations in wind speeds and directions may have been intensified by the local mountainous topography. It had been reported that on two flights earlier in the day, the aircraft had encountered strong wind gusts and turbulence in the vicinity of Linda Lake. The temperature was approximately 8C. It is a standard practice to maintain a higher-than-normal indicated airspeed throughout the approach and landing when operating an aircraft in strong and variable winds, so as to maintain effective control response during fluctuations in airspeed and to prevent an inadvertent stall. 1.8 External Load One set of moose antlers was found secured to the right float diagonal strut and entrance step. The antlers spanned 53inches from tip to tip. They had been tied parallel to the longitudinal axis of the aircraft, above the float deck, with the palms and tips up. Piper PA-18 aircraft are commonly used by hunting outfitters to transport animal antlers. The cabin space in the PA-18 precludes the carriage of large moose and caribou antlers inside the aircraft; therefore, the antlers are often carried externally, either on float struts, or, in the case of wheel-equipped aircraft, on the wing struts. The carriage of external loads is not approved in the PA-18 type certificate or in any PA-18STC. The pilot had flown moose antlers externally on this type of aircraft many times in the past. External loads create parasite drag, which degrades aircraft performance. Animal antlers are not streamlined and, considering their size, may, therefore, create unusually high drag. Several experienced PA-18pilots were contacted to determine the performance degradation associated with carrying antlers as external loads. The comments varied widely, with some pilots reporting little degradation in overall performance and others reporting significant degradation. One highly experienced pilot advised that moose antlers must be secured with the palms down and the tips resting on the float deck, so as to reduce the airflow disturbance over the tail. No flight test data were found that documented PA-18 float plane performance with externally mounted antlers. In April 1997, the Canadian Aviation Regulation Advisory Council (CARAC) started to review the issue of the carriage of external loads on aircraft. CAR703.25 states that except where carriage of an external load has been authorized in a Type Certificate or Supplemental Type Certificate (TC/STC), no operator shall operate an aircraft to carry an external load with passengers on board. The CARAC External Loads Working Group recognized that CAR703.25, while prohibiting passengers, does not prohibit unauthorized external loads when there are no passengers, and that the regulation could be misinterpreted as allowing external loads without passengers. The working group's final report recommended the deletion of CAR 703.25 and the revision of CAR to accommodate external load operations with/without passengers, private and commercial operations, for aeroplanes and helicopters whose flight authority is not validated by a TC/STC. The CAR has not been revised to accommodate the recommendations contained in the External Loads Working Group's final report. Transport Canada Commercial and Business Aviation Advisory Circular No.0209 informs float plane operators of an exemption to CAR703.25. The purpose of the exemption is to permit float plane operators to carry passengers and an external load without authorization in a TC/STC, provided certain conditions are met. The exemption frees the operator from having to comply with the passenger restriction imposed by CAR703.25; however, there is no specific reference to operations where external loads are carried without passengers on board. The exemption is subject to several conditions. The Company Operations Manual must contain direction to flight crews concerning operations with external loads, and a one-time proving flight is required for each particular type of load. As well, pilots must be briefed and trained in accordance with Section723.88 of the Canadian Air Services Standard. The operating limitations include a requirement to reduce the maximum gross take-off weight of the aircraft by twice the weight of any external load. Airworthiness Manual Advisory 500/10 provides similar appropriate guidelines for the operation of aircraft carrying external loads. Scenic Air Services Ltd.'s Company Operations Manual contained contradictory information regarding the carriage of external loads. Section3.16 of the manual stated that pilots shall not fly company aeroplanes with an external load and passengers on board, unless authorized by a TC/STC. Section5.11.1 required that pilots be instructed on the carriage of external loads on floats during initial technical ground training. Section5.6 stated there would be no carriage of external loads. There was nothing found to indicate that a moose antler, external-load, proving flight had ever been accomplished. The TSB Aviation Safety Information System database (1976to2004) contains records of, at minimum, 17occurrences that have involved float planes carrying external loads. The occurrences involved nine private operators, six commercial operators, and two government operators. A review of the circumstances surrounding 16of these 17occurrences indicated that the presence of an external load was a contributing factor, due to the adverse effect of the external load on the aircraft's aerodynamics and performance. Fourteen of the occurrences were accidents due to a loss of control that resulted in a stall or spin. The accidents resulted in 19fatalities and 6serious injuries. (SeeAppendixA - Accidents Involving External Loads.) 1.9 Communications The aircraft was on a company flight itinerary, and there was no NAV CANADA involvement. 1.10 Aerodrome Information Linda Lake is a small, teardrop-shaped lake, located at 5951'north and 13014'west. The surface altitude is 4100feet above sea level. The lake is 0.7nautical miles (nm) long and oriented north/south in a mountain valley. The wreckage was found on the northeast shoreline, approximately 0.2nm south of the north end of the lake. 1.11 Medical Information Post-mortem examination of the pilot did not reveal any indication that incapacitation or any physiological factor had affected his performance. Ibuprofen, in an amount that was too small to quantify, was detected during toxicology testing. The amount present would not have affected the pilot's performance. Tests for the presence of other common drugs and alcohol were negative. 1.12 Survival Aspects Although the pilot's seat was fitted with a four-point lap-belt/shoulder harness restraint system, the shoulder harness was not worn. The shoulder straps were anchored to the seat frame at the lower end of the seat back and extended upward along the seat back, over the top of the seat back, and down the front of the occupant when fastened. The Small Airplane Crashworthiness Design Guide states that shoulder straps should pass over the shoulders in a horizontal plane, or at any upward (from shoulders to pull-off point) angle not to exceed 30, and that any installation that causes the straps to pass over the shoulders at an angle below the horizontal adds additional compressive force to the occupant's spine during an accident. The pilot was reportedly aware of the deficiencies in this shoulder harness design and was reportedly in the habit of not wearing the shoulder harness for that reason. The autopsy identified that the cause of death was massive cranial and thoracic traumatic injuries. It was the pathologist's opinion that the injuries to the neck and basal skull regions were induced by severe deceleration forces rather than by contact with cabin structure, and that these injuries would not likely have been prevented by the use of the shoulder harness. 1.13 Organizational and Management Information At the time of the occurrence, Scenic Air Services Ltd. was a small, privately owned company, employing three or fewer people and offering fixed-wing air services to the public in accordance with CAR702, AerialWork, and CAR703, Air Taxi Operations. The company operated two PiperPA-18-150 aircraft, seasonally, for outfitters based in northern British Columbia and the Northwest Territories. The original Air Operator Certificate (AOC) was issued in July1990. The company changed ownership on 31December1996. The AOC was suspended 14March1997 because the company did not employ a qualified Operations Manager, a Chief Pilot, and a Maintenance Manager, and it had not established an operations manual, as required by the new CARs. The AOC was reinstated 23July1997, following the approval of the new Company Operations Manual and the appointment of the pilot involved in this occurrence to the required administrative positions. On 11July2002, the company received a Certificate of Approval to operate an Approved Maintenance Organization (AMO). At the time of the accident, the accident aircraft was registered commercially and the second PA-18 aircraft was registered privately. 1.14 Transport Canada Overview Inspections and audits are key components in the Transport Canada safety oversight program. Transport Canada Civil Aviation (TCCA) Publication TP13750E states that Commercial and Business Aviation (CBA) inspection and audit functions confirm for TCCA that a Canadian aviation document holder is operating in compliance with regulatory requirements. A company receives its AOC on the basis that the program submitted for TCCA approval meets regulatory requirements. Emphasis is placed on the operator's control manuals, such as the Company Operations Manual, to ensure that the content adequately addresses program control. Transport Canada CBA inspections and audits are intended to be completed at regular intervals. The Transport Canada Manual of Regulatory Audits requires commercial operators to be audited at least once every three years, with an option of extending the interval to five years in 703operations, where risk factors are deemed low. The risk factors that may trigger Transport Canada to consider an audit outside of the normal schedule include a poor accident or safety record within a company, a merger or takeover, and safety concerns relating to management history and practices. CBA inspectors had not performed an audit on Scenic Air Services Ltd. since prior to the issue of the original AOC in1990. An operations audit had been scheduled to take place on 03July2001; however, it was postponed. A Transport Canada Maintenance and Manufacturing regulatory audit had been conducted from 08to 10July2002, prior to Scenic Air Services Ltd. receiving certification as an AMO. The audit findings highlighted several concerns relating to maintaining staff training records and the lack of initial and recurrent staff training. The accident aircraft was not available for examination by the auditors at the time of the audit. The operator had one reported accident in 1995 that resulted in substantial damage to the aircraft (TSBoccurrenceNo.A95W0145). The company came under new ownership in early1997. The company had a second accident in2000 that also resulted in substantial aircraft damage (TSBoccurrenceNo.A00W0187). There were two additional incidents in2000, one involving an aircraft that nosed down during a short-field take-off, resulting in propeller and cowling damage, and a second involving an unsecured aircraft that rolled in strong winds and collided with a fuel truck. The following TSB Engineering Laboratory report was completed and is available upon request: LP 133/03 - Right Magneto P-Lead